Cassius Marcellus Clay, Jr. is fondly remembered as one of the greatest boxers of all time following his 21-year-long career. At a young age, the fighter became the heavyweight champion of the world three times and gave himself the now-iconic name, Muhammad Ali.

During his time in the spotlight, Ali not only caused shock-waves in boxing, but outside the ring he also challenged mainstream America with his ongoing battle for black and Muslim equality.

Early on in his career, Ali joined the religious organization The Nation Of Islam and gave himself what he referred to as his “slave name.”

“Muhammad means ‘worthy of all praises’ and Ali means ‘most high,’” he is heard saying in an early interview before his tragic 2016 death.

“It was a political and social awakening,” recalls Ali’s friend and biographer, Thomas Hauser, in REELZ’s new docuseries, Autopsy: Muhammad Ali.

“He said ‘I wanna have a name of culture,” added Khalilah Ali, Muhammad Ali’s second wife, in the show teaser. “I wanna have a name of respect and dignity.”

Autopsy: Muhammad Ali airs Sunday, April 1 at 8:00 ET / PT on REELZ.